Two-stroke internal-combustion engine



R. A. WILLIAMS. TWO-STROKE INTERNAL COMBUSTION ENGINE. APPLICATION FILED FEB. 1', 19m.

, 1,354,931 Patented Oct. 5,1920.

R. A. WILLIAMS. TWO-STROKE INTERNAL COMBUSTION ENGINE.

APPLICATION FILED FEB-1.1918.

B Mu

UNITED STATES PATENT OFFICE.

ROBERT ARTHUR WILLIAMS, 0F LLANWNDA, NEAR CARNARVON', WALES.

Application filed February 1, 1918.

To all whom it may concern Be it known that I, Bonner ARTHUR WVIL LIAMS, a subject of the King of Great Britain and Ireland, and resident of Porthyr-Aur, Llanwnda, near Carnarvon, North Vi ales, have invented new and useful Improvements in and Relating to Two-Stroke Internal-Combustion Engines, of which the following is the specification.

This invention relates to improvements in two-stroke internal combustion engines having as their object to provide better means than have hitherto been employed in engines of this type for delivery of air supply under initial compression in order to scavenge the working cylinderof its waste gases before. delivery thereto ofv the new charge or air mixed with liquid fuelso as to insure that there shall be no waste of fuel by the passage of same through the exhaust port before compression. A further object of the invention is to provide better means for supplying and mixing the liquid fuel with the air for combustion just prior to its delivery to the working cylinder.

I provide a delivery pipe or channel from the air compressor or pump formed in such manner and of such area at the junction of the said transfer pipe with the cylinder wall, that it embraces two separate ports or passages opening into the cylinder. The one of smaller area is first opened or uncoveredby the piston in its working or outstroke. Through this port air alone .is first delivered to the working cylinder to scavenge same. The separate passage supplying air only extends for some distance into the said transfer passage or pipe so as to insure that no fuel is delivered by the said port first uncovered by the piston. The air may bepumped and delivered in the usual manner by the opposite side of the working piston and the crank chamber, or by a separate cylinder and piston connected to the same crank shaft as the working cylinder or by a separate rotary pump.

I provide arranged centrally within'that division of the transfer passage forming a continuation of the second port uncovered by the piston, a nozzle or jet for the de livery of liquid fuel under pressure, the jet being arranged also centrally within said passage. I providea closed tank for the liquid. fuel which fed by any suit as frem a main tank lion-t Specification of Letters Patent.

Patented Oct. 5, 1920.

Serial No. 214,938.

feed of the usual kind, but with a non-rcturn valve between the two tanks. I provide a pipe connection from the said air delivery channel to the top of the liquid fuel supply tank, so that the air pressure and varying pressures within the said channel are transmitted to the surface of the liquid within same in order to deliver the liquid to the said jet or nozzle. I provide a needle valve fitting the orifice of the said jet, the spindle of which passes through a gland on the wall of the said channel to the outside of the said wall, and is fitted with a knurled head handle for turning same.

The pressure transmitted to the surface of the liquid fuel in the tank by the described means causes a jet of liquid fuel to be delivered mixed with air to the working cylinder following each compression stroke of the pump.

In a double acting two stroke engine having the exhaust port or ports and mixture or new charge port or ports placed midway in the cylinder, I provide one mixture or the like delivery port and two scavenging air supply ports one on each side of the central mixture port, the three ports being arranged longitudinally in the cylinder wall.

And in order that my invention may be completely understood reference should be inade to the accompanying sheets of drawings which illustrate the preferred mode of carrying the invention into effect. It will be understood that the drawings are to a large extent diagrammatic.

Figure l is an elevation, part section, of a double acting two stroke engine having an air compressor mounted on the same crank chamber.

'Fig, 2 is a sectional elevation through the working cylinder.

Fig. 3 is a sectional plan through the center of the working cylinder and through the air compressor.

Fig. 4 is a diagram to show more clearly the method of working and the operation of the fuel feed.

Fig. 5 is a view of the inlet port to the working cylinder as it would appear from the interior thereof.

In Figs. 1, 2 and 3, the air supply in the double acting two stroke internal combustion engine shown is provided by'the air pump or compressor, the piston of which is connected to the same crank shaft as that A is the double acting working cylinder having the piston B therein adapted to have an explosion take place on each side of it, and provided with deflectors or battle plates (J, G on the one side, and sim ilar'defiectors or bafile plates C C on the other side.

D 'is the inlet port for the delivery of mixture, the one inlet port serving in this construction to supply the working charge to both sides or the double acting piston. The air compressor cylinder E of usual construction is also double acting, it being provided withsuction and delivery valves of usual construction on both sides of the working piston E therein for this purpose. The compressed air supply is delivered by the pipe F, see the diagram Fig. 4, and the sectional plan, Fig; 3, both ends 01": the compressor delivering to the one pipe F. The air supply and pressure are controlled by any suitable valve fitted within the pipe F between the compressor and the working cylinder, a throttle valve G of the ordinary pattern being shown for this purpose in Fig. 4. The piston B inapproaching the end of its stroke at either end first uncovers thescavenging air port H or H the port H being provided for the upper end of the working cylinder, and the port H for the lower end. The exhaust port I which is common to both working ends of the cylinder begins to open by the movement of the Working piston simultaneously with the opening of the scavenging air port H with the piston in the position shown in Fig. 4.

in order to displace and eject a portion of the exhaust gases from the combustion chamber at the lower end of the cylinder through the exhaust port 1 before the mixture or new charge port D is uncovered. The continued movement of the piston to ward the end of the stroke uncovers this delivery port D and mixture or new charge 'is delivered to the working cylinder simultaneously with the scavenging air from the scavenging air port until the piston reaches the end of the stroke as shown in Fig. l. A similar operation takes place when the piston 13 approaches the end of the stroke at the lower end of the cylinder, but the I scavenging air port H first comes into op- 'eration, the mixture or new charge port D then serves to supply the upper end of the working cylinder, and the same series of operat ons take place as in the lower end. The center of the port D 15 midway in the stroke of the piston B. K is the petrol or 7 other liquid fuel supply tank which as shown in the diagram, Fig. 4, is connected 7 by the pipe K to the compressed air supply channel F. By this means the air pressure in the supply channel F is conveyed to the surface of the liquid fuel in the tank 7 K. Theair pressure in the channel F varies, belng at a maximum when the compressor piston E is at the end of its stroke. In Fig. 1, the pump or compressor piston E is at the lower end or" its stroke, while the working piston B is at its upper end. As the pump piston approaches the end of its stroke, the air pressure conveyed by the pipe K and transmitted to the surface of the petrol or the like tank K, forces the liquid ttuel by the pipe K connected at the bottom of the tank K to the pipe K andthe jet or nozzle 15*, this jet or nozzle being fitted centrally within the pipe K which pipe is securely fined within the port D opening into the cylinder wall. The nozzle K is provided with the adjustable screwdown needle valve I.) having the knurled head L at its outer end. The thread on the end of the needle L fits a screwed cover L closing a packingjgland L"; By this means theretore,a spray of liquid fuel is delivered through the port D directly the wor" piston B uncovers this port, this pos of the working-pisten coinciding with the maximum air pressure on the surface of the liquid in the tank K. This pressure and therefore the quantity of liquid fuel delivered by the nozzle K may be controlled by the throttle valve G, which valve may be placed at any suitable position in the air de liverv pipe F and may be of any suitable construction; Additional control of the supply of liquid fuel as also of scavenging air may be provided by the throttle valve M placed in the exhaust pip-e 1 The tank K is connected to the main supply tank (not shown) of liquid fuel by the pipe 0 which pipe is provided with the small nonreturn valve 0 that permits liquid fuel to flow into the tank K by the suction of the pump or by gravity, but prevents the passage ot either air or liquid fuel from the tank K to the pipe 0, and therefore prevents the escape of air or fuel from the tank K to the main supply tank (not shown).

It will be observedthat by this construc tion, the supply of liquid fuel is provided only at the time it is required. namely, at the opening or uncovering of the port J by the working piston and that the control provided by the throttle valve G or by the valve M necessarily provides control simultaneously of the air supply for scavenging purposes, the air supply for combustion, and also of the feed of the liquid fuel. this latter supply being dependent upon and controlled by the air pressure in the pipe F.;

Further in the construction shown applied to a double acting engine the arrangement serves to supply and control the supply of fuel and air for both ends of the double acting engine.

As shown in Figs. 1 and 8, the eXhaust pipe 1 may be fitted surrounding a portion of the air delivery pipe F in order to heat same.

What I do claim as my invention and desire to secure by Letters Patent is 1. The combination of a two stroke internal combustion engine having two intake ports in the cylinder wall, one for scavenging air and the other for fuel, said ports being controlled by the piston and arranged so that the scavenging air port will be uncovered by the piston advance of the fuel port, an air compressor, and means for supplying compressed air from said pump simultaneously to both of said ports, said means comprising a single pipe leading from the compressor and connected with both of said'ports, a fuel feeding nozzle adjacent the fuel feeding port, and means for supplying fuel under pressure to said nozzle.

2. The combination in a two stroke internal combustion engine having two intake ports in the cylinder wall, one for scavenging air and. the other for fuel, said ports being arranged so that the scavengin port will be opened to the cylinder in advance of the fuel port, an air compressor connected with both of said ports, a fuel tank, a fuel jet associated with the fuel port, a conduit leading from the fuel tank to the jet, and means connecting the fuel tank with the compressor whereby air pressure is supplied to the surface of the liquid in the fuel tank to feed the same to the nozzle.

3. The combination in a two stroke in.- ternal combustion engine having two intake ports in the cylinder well, one for scaven ging air and the other for -said ports being arranged so that the scavenging air iort will be opened to the cylinder in advance of the fuel port, an air compressor connected with both of said ports, fuel jet associated with the fuel port, a fuel supply tank, means connecting the fuel tank with the compressor whereby air pressure is supplied to the surface of the liquid in the fuel tank to feed the fuel to the nozzle, and means for varying the air pressure whereby the liquid fuel supply is simultaneously varied and controlled.

l. The combination in a two stroke internal combustion engine having two intake ports in the cylinder wall, one of said ports being a scavenging air port and the other for fuel, said ports being arranged to be opened one in advance of the other, an air compressor, a pipe leading from the discharge end of the compressor and communicating with both the scavenging air and fuel air port, a fuel supply tank, a fuel nozzle associated with the fuel port, a pipe connecting said fuel nozzle with the lower part of the fuel tank, and a pipe connecting the upper porton of the tank with the air pipe, and means for varying the air pressure in the air pipe whereby the liquid fuel supply is simultaneously varied and controlled.

5. The combination in a two stroke internal combustion engine having two intake ports in the cylinder wall, one of said ports being a scavenging air port and the other for fuel, said ports being arranged to be opened one in advance of the other, an air compressor, a pipe leading from the discharge end of the compressor and communieating with both the scavenging air and fuel port, a fuel supply tank, a fuel nozzle associated with the fuel port, a pipe connecting said fuel nozzle with the lower part of the fuel tank, and a pipe connecting the upper portion of the tank with the air pipe, means for varying the air pressure in the air pipe whereby the liquid fuel supply is simultaneously varied and controlled, and a screw or needle valve for regulating the size of the orifice of the fuel nozzle.

6. The combination in an internal combustion engine, of means for supplying compressed air to the engine, a fuel port, a fuel nozzle associated with said port, a fuel tank, a fuel supply pipe connected with the fuel tank, a non-return valve permitting the pasof fuel from the fuel supply pipe to the fuel tank but preventing the passage of air or liquid from the pressure tank into the supply pipe, and means connecting the fuel tank to the compressed air supply whereby liquid fuel will be fed to the nozzle by air pressure.

7. The combination in a two stroke in ternal combustion engine having a central fuel port common to both working ends of the cylinder, and a pair of scavenging air ports, the fuel port and air ports being controlled by the piston, said air ports being arranged one on each side of the central fuel port longitudinally of the cylinder so that said scavenging ports deliver respectively to opposite sides of the working piston, in advance of the fuel ports, an air compressor, a single pipe connecting the delivery of the air compressor with all of said ports, a nozzle associated with the central fuel port, and means for supplying liquid fuel to the nozzle.

R OBERT ARTHUR WILLIAMS.

Witnesses I. D. Roors, l. MnLLoR. 

